COLLISION AVOIDANCE APPARATUS

Collision avoidance apparatus for assessing manoeuvres of a first vehicle (6) to avoid collision with other vehicles (22) in which closed regions are computed respectively associated with the other vehicles and which, if avoided by the first vehicle, will assure that the latter will not pass closer to the other vehicles than a predetermined distance (CPA). The periphery of each of said regions is defined by lines joining the following points: PA1 the point (49) at which the first vehicle (6) would be at said predetermined distance (CPA) from the other vehicle (22) in question when on a heading to cause the other vehicle (22) to pass ahead (ahead CPA joint); PA1 the possible point (51) of collision (PPC) of the first vehicle (6) and the other vehicle (22) based on the present speeds of the two vehicles and the present heading of the other vehicle; the point (52) at which the first vehicle (6) would be at said predetermined distance (CPA) from the other vehicle (22) in question when on a heading to cause the other vehicle to pass astern (astern CPA point); PA1 and the points of intersection (56,57) of a line parallel to the heading of the other vehicle (22), and spaced from it by said predetermined distance (CPA on the side nearest to the first vehicle (6), with said astern and ahead headings of the first vehicle (6).